What is Base64 encoding?

Base64 encoding is a binary-to-text encoding scheme defined by RFC 4648. It converts raw binary bytes or text into an ASCII string using a set of 64 printable characters (A-Z, a-z, 0-9, +, / or -, _).

Is Base64 considered encryption or security?

No. Base64 is NOT encryption and provides zero security or confidentiality. Anyone can decode a Base64 string back into plain text. Base64 is merely a format translation for safe data transport across text-only protocols.

What is the difference between Standard Base64 and URL Safe Base64?

Standard Base64 uses + and / characters along with = padding. In web URLs, + can be interpreted as a space and / as a directory path. URL Safe Base64 replaces + with - (hyphen) and / with _ (underscore), and optionally strips = padding to prevent URL corruption.

Why does Base64 increase file size by ~33%?

Base64 represents 3 binary bytes (24 bits) using 4 ASCII characters (6 bits per character). Because 4 characters are used to represent 3 bytes, the output file size is always approximately 33.3% larger than the original raw data.

What does the equals sign (=) mean at the end of a Base64 string?

The = sign is padding used to align the encoded output string length to a multiple of 4 characters. If the original input data length in bytes is not divisible by 3, one or two = characters are appended to indicate remaining padding bits.

Can ToolMono decode Base64 strings that are missing padding?

Yes. ToolMono features an automatic padding repair engine that automatically appends missing = or == padding characters prior to decoding.

Are my files, text, or images sent to ToolMono servers?

No. Absolutely zero text, images, PDFs, or files are ever uploaded to any external server. 100% of encoding, decoding, auto-detection, and image rendering occurs locally inside your web browser.

How do I encode an image to Base64 for HTML or CSS?

Drag and drop your PNG, JPEG, SVG, or WebP image into ToolMono. The tool will convert the image into a complete Data URI (e.g. data:image/png;base64,...), which you can copy and paste directly into HTML tags or CSS background-image rules.

Which character encodings does ToolMono support?

ToolMono supports UTF-8, UTF-16, ASCII, and Latin-1 character set encodings, ensuring proper multi-byte Unicode and emoji serialization.

How do I decode Base64 data back to a downloadable file?

Paste your Base64 payload or Data URI into the editor and click 'Download Binary' or 'Save Image'. ToolMono converts the Base64 bytes back into a native Blob and triggers a local file download.

A Data URI is a uniform resource identifier scheme that allows small files (like images, icons, or fonts) to be embedded inline in web pages using the syntax `data:[ ][;base64], `.

RFC 4648 is the official Internet Engineering Task Force (IETF) standard specification for Base16, Base32, and Base64 Data Encodings, defining character alphabets, padding rules, and URL-safe variants.

How does Base64 work in MIME email attachments?

SMTP email protocols were originally built for 7-bit ASCII text. Base64 is used to encode 8-bit binary email attachments (images, PDFs, documents) into safe 7-bit ASCII text for reliable transmission.

Are JSON Web Tokens (JWT) Base64 encoded?

Yes. The Header and Payload sections of a JWT are JSON objects encoded using Base64Url (URL-safe Base64 without padding).

Can I encode large files with ToolMono?

Yes. ToolMono uses memory-efficient chunked Uint8Array processing to encode and decode large text and binary files smoothly without freezing your browser interface.

What happens if a Base64 string contains invalid characters?

ToolMono offers strict validation mode or automatic character sanitization to clean illegal whitespace, newlines, or non-base64 symbols before decoding.

How can I wrap Base64 output into lines of 64 or 76 characters?

Enable the Line Break option under Advanced Options and select 64 (MIME standard), 76 (PEM standard), or enter a custom line length.

Does ToolMono store my conversion history?

ToolMono maintains an optional local workspace history stored exclusively in your browser's private `localStorage`. You can copy, reuse, or clear history anytime with one click.

Can ToolMono Base64 be used offline?

Yes. Once loaded in your browser, ToolMono functions 100% offline without an active internet connection.

What is Base64 encoding?

Base64 encoding is a binary-to-text encoding scheme defined by RFC 4648. It converts raw binary bytes or text into an ASCII string using a set of 64 printable characters (A-Z, a-z, 0-9, +, / or -, _).

Is Base64 considered encryption or security?

No. Base64 is NOT encryption and provides zero security or confidentiality. Anyone can decode a Base64 string back into plain text. Base64 is merely a format translation for safe data transport across text-only protocols.

What is the difference between Standard Base64 and URL Safe Base64?

Standard Base64 uses + and / characters along with = padding. In web URLs, + can be interpreted as a space and / as a directory path. URL Safe Base64 replaces + with - (hyphen) and / with _ (underscore), and optionally strips = padding to prevent URL corruption.

Why does Base64 increase file size by ~33%?

Base64 represents 3 binary bytes (24 bits) using 4 ASCII characters (6 bits per character). Because 4 characters are used to represent 3 bytes, the output file size is always approximately 33.3% larger than the original raw data.

What does the equals sign (=) mean at the end of a Base64 string?

The = sign is padding used to align the encoded output string length to a multiple of 4 characters. If the original input data length in bytes is not divisible by 3, one or two = characters are appended to indicate remaining padding bits.

Can ToolMono decode Base64 strings that are missing padding?

Yes. ToolMono features an automatic padding repair engine that automatically appends missing = or == padding characters prior to decoding.

Are my files, text, or images sent to ToolMono servers?

No. Absolutely zero text, images, PDFs, or files are ever uploaded to any external server. 100% of encoding, decoding, auto-detection, and image rendering occurs locally inside your web browser.

How do I encode an image to Base64 for HTML or CSS?

Drag and drop your PNG, JPEG, SVG, or WebP image into ToolMono. The tool will convert the image into a complete Data URI (e.g. data:image/png;base64,...), which you can copy and paste directly into HTML tags or CSS background-image rules.

Which character encodings does ToolMono support?

ToolMono supports UTF-8, UTF-16, ASCII, and Latin-1 character set encodings, ensuring proper multi-byte Unicode and emoji serialization.

How do I decode Base64 data back to a downloadable file?

Paste your Base64 payload or Data URI into the editor and click 'Download Binary' or 'Save Image'. ToolMono converts the Base64 bytes back into a native Blob and triggers a local file download.

A Data URI is a uniform resource identifier scheme that allows small files (like images, icons, or fonts) to be embedded inline in web pages using the syntax data:[ ][;base64], .

RFC 4648 is the official Internet Engineering Task Force (IETF) standard specification for Base16, Base32, and Base64 Data Encodings, defining character alphabets, padding rules, and URL-safe variants.

How does Base64 work in MIME email attachments?

SMTP email protocols were originally built for 7-bit ASCII text. Base64 is used to encode 8-bit binary email attachments (images, PDFs, documents) into safe 7-bit ASCII text for reliable transmission.

Are JSON Web Tokens (JWT) Base64 encoded?

Yes. The Header and Payload sections of a JWT are JSON objects encoded using Base64Url (URL-safe Base64 without padding).

Can I encode large files with ToolMono?

Yes. ToolMono uses memory-efficient chunked Uint8Array processing to encode and decode large text and binary files smoothly without freezing your browser interface.

What happens if a Base64 string contains invalid characters?

ToolMono offers strict validation mode or automatic character sanitization to clean illegal whitespace, newlines, or non-base64 symbols before decoding.

How can I wrap Base64 output into lines of 64 or 76 characters?

Enable the Line Break option under Advanced Options and select 64 (MIME standard), 76 (PEM standard), or enter a custom line length.

Does ToolMono store my conversion history?

ToolMono maintains an optional local workspace history stored exclusively in your browser's private localStorage. You can copy, reuse, or clear history anytime with one click.

Can ToolMono Base64 be used offline?

Yes. Once loaded in your browser, ToolMono functions 100% offline without an active internet connection.

Base64 Encoder Decoder

Name: Base64 Encoder Decoder Online - Convert Text & Data | ToolMono
Author: ToolMono Engineering Team

Free, 100% client-side Base64 encoder and decoder. Convert text, strings, and data to Base64 or Base64URL instantly with UTF-8 support, padding controls, and client-side processing.

Category: EncodingAuthor: ToolMono Engineering TeamLast Updated: July 29, 2026Reading Time: ~5 min readStatus: stable

🔐 Base64 Encoder & Decoder⚡ Instant Processing📁 File Support🔒 100% Client-side🛡 RFC 4648 Compliant✨ Free Forever

Client-Side Processing — Your input stays in your browser.

Base64 Format

Character Encoding

Padding Mode (=)

Line Length Chunking

Input Editor

Plain Text / File

36 chars•38 B

Output Result

Base64 String

0 chars•0 B

Complementary Workflows:

URL Encoder•URL Parser•JWT Decoder

Overview

The ToolMono Base64 Encoder & Decoder is an enterprise-grade, privacy-first web developer utility designed for software engineers, backend developers, frontend architects, security researchers, and DevOps specialists. Base64 encoding is an open RFC 4648 specification created to represent arbitrary binary data or multi-byte unicode strings in a universally compatible ASCII text format.

Many legacy network protocols—such as 7-bit SMTP email transmission, HTTP header values, URL query parameters, and JSON payloads—cannot safely transmit raw binary bytes or unescaped control characters without data corruption. By translating 8-bit binary sequences into 6-bit index offsets mapped to 64 printable ASCII characters, Base64 ensures flawless data transmission across all network boundaries.

Unlike online converters that transmit sensitive payloads, API tokens, or internal images to remote backend logging servers, ToolMono executes 100% client-side Base64 processing using native browser Web APIs (TextEncoder, TextDecoder, FileReader). Your text, files, and images never leave your machine sandbox. For complementary developer workflows, explore our URL Encoder & Decoder, JWT Decoder, JSON Formatter, and Hash Generator.

Base64 Encoding & Decoding Engine

ToolMono features a modern, bi-directional Base64 engine built for extreme performance, compliance, and developer convenience. The engine handles text and file conversions with zero server lag:

Auto-Detect Mode

Intelligently inspects input text to automatically distinguish between raw plain text (to encode) and Base64/Data URI strings (to decode).

Multi-Character Encodings

Full support for UTF-8 (emojis and global unicode characters), UTF-16, 7-bit ASCII, and Latin-1 (ISO-8859-1) character sets.

RFC 4648 URL Safe Mode

Instantly converts standard Base64 characters (+ and /) into URL-Safe characters (- and _).

Padding Repair Engine

Automatically validates padding alignment and repairs missing = trailing characters for malformed inputs.

File Support & Drag-and-Drop

Universal File & Binary Payload Converter

Base64 is not limited to plain text strings. ToolMono allows you to drag & drop any document or binary asset directly into your browser. The engine converts the file into raw Base64 or formatted Data URIs instantly:

🖼️ Images (PNG, JPG, WebP)

🎨 Vector SVGs

📄 PDF Documents

📊 JSON / XML / CSV

💾 Binary Executables

📋 Clipboard Image Paste

📂 Drag & Drop Target

🔒 100% Local FileReader

Image Preview & Data URI Generation

Automatic Data URI & Image Inspection

When decoding Base64 strings or pasting data:image/... payloads, ToolMono automatically inspects the magic byte headers to render a live image preview alongside key image metadata:

Live Image Canvas Render
Dimensions (Width x Height in pixels)
Calculated File Size (KB/MB)
Detected MIME Type (image/png, image/jpeg, image/webp, image/svg+xml)
One-click Image File Download

HTML & CSS Inline Embedding Syntax

Embedding small Base64 images directly into HTML or CSS eliminates additional HTTP network requests for icons and badges:

<!-- HTML Inline Image -->
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA..." alt="Logo" />

/* CSS Background Image */
.button-icon {
  background-image: url('data:image/svg+xml;base64,PHN2Zz4...');
}

Advanced Options & Configuration

Option	Setting Values	Specification & Use Case
Base64 Format	Standard (+) / URL Safe (-_)	Replaces + and / with - and _ to prevent URL query parameter corruption.
Character Set	UTF-8 \| UTF-16 \| ASCII \| Latin-1	Controls byte serialization for non-ASCII characters, emojis, and legacy systems.
Padding Behavior	Auto Repair \| Remove \| Restore	Manages trailing = padding characters required by RFC 4648 alignment rules.
Line Wrapping	None \| 64 chars \| 76 chars \| Custom	Wraps Base64 output into lines. 64 chars for MIME email, 76 chars for PEM keys.

Validation Statistics & RFC 4648 Compliance

RFC 4648 Verified

Compliance Status

Monitors invalid characters, unaligned string lengths, and illegal whitespace to verify RFC compliance.

Exact Bytes

Character & Byte Counters

Calculates precise input character count, input byte size, output character count, and output byte size.

+33.3% Overhead

Expansion Ratio

Displays exact payload overhead ratio (+33.3% for encoding, -25.0% for decoding).

Developer Code Examples (11 Languages)

Select your target programming language to view production-ready Base64 encoding and decoding snippets:

JavaScript (Browser Native)

// JavaScript (Browser) - Text & Data URI Base64 Encoding/Decoding

// 1. Encode UTF-8 Text to Base64 (Standard RFC 4648)
function encodeBase64(text) {
  const bytes = new TextEncoder().encode(text);
  let binary = "";
  for (let i = 0; i < bytes.byteLength; i++) {
    binary += String.fromCharCode(bytes[i]);
  }
  return btoa(binary);
}

// 2. Decode Base64 string to UTF-8 Text
function decodeBase64(b64) {
  // Strip whitespace and fix missing padding
  let clean = b64.trim().replace(/[\r\n\s]/g, "");
  while (clean.length % 4 !== 0) clean += "=";
  
  const binary = atob(clean);
  const bytes = new Uint8Array(binary.length);
  for (let i = 0; i < binary.length; i++) {
    bytes[i] = binary.charCodeAt(i);
  }
  return new TextDecoder("utf-8").decode(bytes);
}

// 3. Convert Standard Base64 to URL-Safe Base64
function toUrlSafeBase64(b64) {
  return b64.replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/g, "");
}

// Usage Example
const encoded = encodeBase64("Hello ToolMono 🚀 Base64");
console.log("Encoded:", encoded); // "SGVsbG8gVG9vbE1vbm8g8J+agCBCYXNlNjQ="
console.log("Decoded:", decodeBase64(encoded));

RFC 4648 Reference Tables

1. Base64 Index Character Map (Values 0–63)

Val	Char	Val	Char	Val	Char	Val	Char
0–25	A–Z	26–51	a–z	52–61	0–9	62	+ (std) / - (url)
63	/ (std) / _ (url)	Pad	= (equals)	Bits	6 bits/char	Overhead	+33.33%

2. Byte Alignment & Padding Examples

Input Text	Input Bytes	Binary (24-bit Groups)	Base64 Output	Padding Status
"Man"	3 bytes	01001101 01100001 01101110	TWFu	No Padding Needed
"Ma"	2 bytes	01001101 01100001 (000000)	TWE=	1 Equals Pad (=)
"M"	1 byte	01001101 (0000000000)	TQ==	2 Equals Pad (==)

What is Base64 & How Does It Work?

Core Concept: Binary-to-Text Mapping

Computers store data in 8-bit bytes (values from 0 to 255). However, traditional networking protocols (such as HTTP query strings, SMTP emails, and XML documents) were originally designed to handle only printable 7-bit ASCII text. Attempting to transmit raw binary bytes (like images or encrypted payloads) over these protocols often resulted in byte truncation or corruption. Base64 solves this by converting 3 binary bytes (24 bits) into 4 printable ASCII characters (6 bits per character).

MIME & Email Attachments

In 1992, the IETF published MIME (Multipurpose Internet Mail Extensions) RFC 2045. Base64 is used to encode binary email attachments (PDFs, images, archives) so they can travel safely across legacy 7-bit SMTP mail servers.

HTTP Basic Authentication

HTTP Basic Auth headers send client credentials formatted as username:password encoded in Base64 within the Authorization: Basic <base64> header. Always use HTTPS to protect this header in transit.

AI Overview Answers

What is Base64?

Base64 is a binary-to-text encoding standard defined by RFC 4648. It translates binary bytes or text into an ASCII string composed of 64 printable characters (A-Z, a-z, 0-9, +, / or -, _).

Is Base64 encryption?

No. Base64 is not encryption. Base64 provides zero security or confidentiality. Anyone can instantly decode a Base64 string back into original text or binary data without a secret key.

What is URL Safe Base64?

URL Safe Base64 replaces the + and / characters with - (hyphen) and _ (underscore) to prevent URL routing and query parameter syntax errors.

Why does Base64 increase file size?

Base64 represents 3 bytes (24 bits) of data using 4 ASCII characters (6 bits per character). This 4-to-3 ratio results in a consistent ~33.3% increase in file size.

How to Use ToolMono Base64

Select Mode

Choose Encode, Decode, or Auto-Detect mode.

Input Data

Type text or drop files (PNG, PDF, SVG, JSON).

Configure Options

Toggle URL Safe (-_), UTF-8/ASCII, or padding repair.

Instant Processing

View live image previews and RFC stats.

Copy / Download

Copy output, download TXT/JSON, or save binary image.

Base64 Best Practices

Use URL Safe Base64 for Web Query Parameters

Always use URL Safe Base64 (- and _) when embedding tokens or parameters in URLs to prevent web server decoding errors.

Limit Data URI Inline Embedding to Small Files (<10KB)

Only embed small icons or SVGs as Data URIs. Base64 encoding large images increases bundle sizes and defeats HTTP caching benefits.

Common Errors & Fixes

Invalid Character in Base64 String

The input string contains non-base64 characters or unescaped line breaks. Enable Auto Padding Repair or strict sanitize mode.

Garbled Decoded Output

The Base64 string decodes to binary data (like an image or PDF) rather than plain text. Check the Image Preview card or click 'Download Binary'.

Tips & Tricks

Direct Clipboard Image Pasting

Copy any image screenshot to your system clipboard and press Ctrl+V inside the input editor to convert it to a Data URI instantly.

Local Storage Workspace History

Your recent Base64 conversions are automatically saved in your browser's private local storage for instant access across browser sessions.

Frequently Asked Questions

Privacy & E-E-A-T Verification

100% Client-Side Privacy & Testing Methodology

ToolMono adheres to rigorous web security standards. Every Base64 conversion, byte calculation, padding validation, and image rendering executes exclusively inside your local browser runtime. No text strings, secret keys, uploaded files, or generated Data URIs are transmitted over HTTP connections or stored on remote servers.

Tested against RFC 4648 & RFC 2045 Specs
Zero External Network Requests
Supports Native Browser Web Crypto & Encoding APIs
100% Offline Capable

References & Standards

RFC 4648: The Base16, Base32, and Base64 Data Encodings

Official IETF standard specification for Base64 and URL-safe Base64 alphabets.

View Documentation

MDN Web Docs: Base64 Encodings Specification

Official Mozilla guide to binary-to-text encoding and browser APIs.

View Documentation

WHATWG HTML Standard: btoa() & atob() Methods

WHATWG recommendation for client-side Base64 conversion.

View Documentation

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URL Encoder & Decoder

Free, 100% client-side URL encoder and decoder. Convert text and query parameters into RFC 3986 percent-encoded strings or decode URLs with smart double-encoding detection and structural URL analysis.

JSON Formatter

Free online JSON formatter, beautifier, and validator. Format, indent, minify, and inspect JSON with real-time syntax error detection in your browser. 100% client-side.

Hash Generator

Generate hashes and file checksums locally in your browser. Compare digests, copy results, and use MD5, SHA-1, SHA-2, SHA-3, BLAKE2, and supported HMAC algorithms.

Online JWT Generator & Token Signer

Build and sign JSON Web Tokens online for API testing and development. Customize JWT claims and generate signed tokens directly in your browser with 100% client-side processing.

Text Compare

Compare two texts online and find differences instantly. Highlight changes line-by-line, word-by-word, or character-by-character with a fast browser-based diff checker.

Regex Tester

Test JavaScript regular expressions with live match highlighting, capture-group inspection, flags, and replacement preview. 100% client-side privacy.

 <img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA..." alt="Logo" /> /* CSS Background Image */ .button-icon { background-image: url('data:image/svg+xml;base64,PHN2Zz4...'); }

Option

Setting Values

Specification & Use Case

Base64 Format

Standard (+) / URL Safe (-_)

Replaces + and / with - and _ to prevent URL query parameter corruption.

Character Set

UTF-8 | UTF-16 | ASCII | Latin-1

Controls byte serialization for non-ASCII characters, emojis, and legacy systems.

Padding Behavior

Auto Repair | Remove | Restore

Manages trailing = padding characters required by RFC 4648 alignment rules.

Line Wrapping

None | 64 chars | 76 chars | Custom

Wraps Base64 output into lines. 64 chars for MIME email, 76 chars for PEM keys.

// JavaScript (Browser) - Text & Data URI Base64 Encoding/Decoding // 1. Encode UTF-8 Text to Base64 (Standard RFC 4648) function encodeBase64(text) { const bytes = new TextEncoder().encode(text); let binary = ""; for (let i = 0; i < bytes.byteLength; i++) { binary += String.fromCharCode(bytes[i]); } return btoa(binary); } // 2. Decode Base64 string to UTF-8 Text function decodeBase64(b64) { // Strip whitespace and fix missing padding let clean = b64.trim().replace(/[\r\n\s]/g, ""); while (clean.length % 4 !== 0) clean += "="; const binary = atob(clean); const bytes = new Uint8Array(binary.length); for (let i = 0; i < binary.length; i++) { bytes[i] = binary.charCodeAt(i); } return new TextDecoder("utf-8").decode(bytes); } // 3. Convert Standard Base64 to URL-Safe Base64 function toUrlSafeBase64(b64) { return b64.replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/g, ""); } // Usage Example const encoded = encodeBase64("Hello ToolMono 🚀 Base64"); console.log("Encoded:", encoded); // "SGVsbG8gVG9vbE1vbm8g8J+agCBCYXNlNjQ=" console.log("Decoded:", decodeBase64(encoded));

Val

Char

Val

Char

Val

Char

Val

Char

0–25

A–Z

26–51

a–z

52–61

0–9

+ (std) / - (url)

/ (std) / _ (url)

Pad

= (equals)

Bits

6 bits/char

Overhead

+33.33%

Input Text

Input Bytes

Binary (24-bit Groups)

Base64 Output

Padding Status

"Man"

3 bytes

01001101 01100001 01101110

TWFu

No Padding Needed

"Ma"

2 bytes

01001101 01100001 (000000)

TWE=

1 Equals Pad (=)

"M"

1 byte

01001101 (0000000000)

TQ==

2 Equals Pad (==)

Input Editor

Output Result

Overview

Base64 Encoding & Decoding Engine

File Support & Drag-and-Drop

Universal File & Binary Payload Converter

Image Preview & Data URI Generation

Automatic Data URI & Image Inspection

HTML & CSS Inline Embedding Syntax

Advanced Options & Configuration

Validation Statistics & RFC 4648 Compliance

Compliance Status

Character & Byte Counters

Expansion Ratio

Developer Code Examples (11 Languages)

RFC 4648 Reference Tables

1. Base64 Index Character Map (Values 0–63)

2. Byte Alignment & Padding Examples

What is Base64 & How Does It Work?

MIME & Email Attachments

HTTP Basic Authentication

AI Overview Answers

What is Base64?

Is Base64 encryption?

What is URL Safe Base64?

Why does Base64 increase file size?

How to Use ToolMono Base64

Select Mode

Input Data

Configure Options

Instant Processing

Copy / Download

Base64 Best Practices

Use URL Safe Base64 for Web Query Parameters

Limit Data URI Inline Embedding to Small Files (<10KB)

Common Errors & Fixes

Invalid Character in Base64 String

Garbled Decoded Output

Tips & Tricks

Direct Clipboard Image Pasting

Local Storage Workspace History

Frequently Asked Questions

Privacy & E-E-A-T Verification

100% Client-Side Privacy & Testing Methodology

References & Standards

RFC 4648: The Base16, Base32, and Base64 Data Encodings

MDN Web Docs: Base64 Encodings Specification

WHATWG HTML Standard: btoa() & atob() Methods

Related Tools

Text Compare

JSON Formatter

Regex Tester Online

Hash Generator

JWT Decoder Online

Online JWT Generator & Token Signer

Related Tools

Input Editor

Output Result

Overview

Base64 Encoding & Decoding Engine

File Support & Drag-and-Drop

Universal File & Binary Payload Converter

Image Preview & Data URI Generation

Automatic Data URI & Image Inspection

HTML & CSS Inline Embedding Syntax

Advanced Options & Configuration

Validation Statistics & RFC 4648 Compliance

Compliance Status

Character & Byte Counters

Expansion Ratio

Developer Code Examples (11 Languages)

RFC 4648 Reference Tables

1. Base64 Index Character Map (Values 0–63)

2. Byte Alignment & Padding Examples

What is Base64 & How Does It Work?

MIME & Email Attachments

HTTP Basic Authentication

AI Overview Answers

What is Base64?

Is Base64 encryption?